Apparatus for coating cores



APPARATUS FOR COATING CORES Filed March 13, 1925 //7 vemor Patented Mar. 4, 1930 UNITED STATES PATENT oFFIce Howm STEIBIBINS DREW, or WESTERN SPRINGS, ILLINOIS, SSIGNQR 'ro' wns' izurtia 'ELEcrRIc COML'PANY, INCORPORATED, or NEW YORK, N. Y., A coRroRA'rIoN or NEW YORK :APPARATUS FOR COATING CORES I Applicationfiled Ill [arch 13, 1925. Serial No. 15,888.

This invention relates to apparatus for p coating cores, and particularly to an im- .proved apparatus for insulating electrical conductors with an organic coating.

One type of organip coating which is applied to copper conductors for the purpose of insulating them electrically consists, in the unapplied' state, of a somewhat viscous material dissolvedin suitable solvents. The

10 material is applied to the wire by passing the wire through a bath thereof in such a manner as to cause a thin coating of the material to adhere thereto. The coating is then baked by passing the coated wire through a 15 heated region where, preliminarily, the solvents are evaporated from the coating and thenthe resulting viscous substance is cured chemically, this second part of the baking consisting of a polymerization, an oxidation, or a combination of polymerization and oxidation of the coating, depending upon its specific nature. expediting such a processfis to apply the liquid material to the wire in a somewhat thicker condition and with less solvent material. If, however, the liquid is too thick, the resulting coat on the wire may be rough or non-uniform .in thickness and therefore commercially undesirable.

Objects of the present invention are to provide an improved apparatus for applying a coating to a core by means of which the coating operation maybe greatly accelerated.

The main feature of the invention conthickened bath of organic insulating material to coat the same, and then passing the coated wire through a bath of mercury, the mercury having the effect of smoothing the coating. Subsequently, the wire may be heat treated for the purpose of curing the coating in a normal manner which will be described more in detail hereinafter.

' The details of the process will be more apparent from the following description taken with the accompanying drawing, in which Fig. 1 is'a schematic representation, partl in section, of a wire insulating machine owing one embodiment-of the invention,

Obviously, one manner of sists in passing the wire through a somewhat Fig. 2 is an enlarged section of a portion I of the mechanism shown in Fig. 1.

Referring now to theaccompanying drawing in which like reference numerals are.

employed to designate similar parts throughout the several views, a chamber 10 is adapted to contain a bath of organic insulating material 11 which is in the proper condition for application to a wire 12. An insulating composition which may be employed with satisfactory results is discussed in U. S. Patent No. 1,101,281, issued June23, 1914, to H. B. Holmes et al. An idler roller 13 is suitably secured within the chamber 10 so that a wire passing therearound will be drawn through the organic material 11 in such a manner as to cause some of said material to adhere thereto. A second chamber 15 having at the bottom thereof a small aperture 16 is adapted to contain a second liquid 17, such as mercury. The mercury is pre vented from flowing through the aperture 16 by the force of its own surface tension.

A vertical tubular oven 18 is adapted to be heated by suitable means, such as electrical current supplied from any suitable source of current connected to terminals 20 and 21 of an associated heating element. An idler roller 23 is suitably secured 'at the upper extremity of the oven 18 to permit the wire to passv a plurality of times through the insulating material 11 and the oven 18, it being noted that the wire may be passed a plurality of times between the rollers 13 and 23. The wire is drawn through the mechanism by suitable means from a supply reel 25, over an idler sheave 26, around the roller 13, through the mercury bath 17 through the oven 18 and over the roller 23, from which it is eventually taken up by suitable take-up mechanism 27 As shown clearly in Fig. 2, as the wire leaves the bath of insulating material 11, some of the material adheres to the wire, but the coating may be thick and uneven. As the coated, wire passes through the mercury bath, however, the coating is smoothed and reduced in thickness by the wiping action of the mercury. This eifect can be varied by regulating the depth of the mercury in the container.

In practicii the method other types of apparatus ma be employed, the particular apparatus shown in the drawing and de scribed above constituting only one means by which the invention may be practiced.

"What is claimedis:

1. 'In a core coating device, a chamber containing material with which the core is to be 'coated, means for passing the core through said chamber to coat said core, a second chamber containing mercury, means for causing a relative movement between said core and said mercury to smooth the coating, and heating means for baking the coating thereon.

2. In a core coating device, a chamber con taining matter with which the core is to be coated, a second chamber containing mercury, said chamber having a small aperture in-a wall thereof to permit the core to bet-,passed through said mercury, means for passing the core through said chambers to preliminarily coat said core and then shape the same, and heating means for baking the coating thereon. c

3. In a core coating device, a chamber containing matter with which the core is to be coated, a second chamber containing mercury, said chamber having a small apperture in a wallthereof for continuously passing the core therethrough, -means for passing the core through said chambers, and means for applying heat to said core to bake the coating thereon.

4. In a core coating device, a chamber containing matter with which the core is to be coated, a second chamber containing mercury, a heated oven for-baking the coating on said core, and means for passing said core through said two chambers and said oven.

In' witness whereof, I hereunto subscribe my name this 4th day of March, A. D. 1925.

' HOWARD STEBBINS DREW. 

